com32/lib/sys/vesacon_write.c

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 2004-2008 H. Peter Anvin - All Rights Reserved
   4  *
   5  *   Permission is hereby granted, free of charge, to any person
   6  *   obtaining a copy of this software and associated documentation
   7  *   files (the "Software"), to deal in the Software without
   8  *   restriction, including without limitation the rights to use,
   9  *   copy, modify, merge, publish, distribute, sublicense, and/or
  10  *   sell copies of the Software, and to permit persons to whom
  11  *   the Software is furnished to do so, subject to the following
  12  *   conditions:
  13  *
  14  *   The above copyright notice and this permission notice shall
  15  *   be included in all copies or substantial portions of the Software.
  16  *
  17  *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18  *   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  19  *   OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  20  *   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  21  *   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  22  *   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23  *   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  24  *   OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  * ----------------------------------------------------------------------- */
  27
  28 /*
  29  * vesacon_write.c
  30  *
  31  * Write to the screen using ANSI control codes (about as capable as
  32  * DOS' ANSI.SYS.)
  33  */
  34
  35 #include <errno.h>
  36 #include <string.h>
  37 #include <com32.h>
  38 #include <minmax.h>
  39 #include <colortbl.h>
  40 #include <console.h>
  41 #include <klibc/compiler.h>
  42 #include "ansi.h"
  43 #include "file.h"
  44 #include "vesa/video.h"
  45
  46 static void vesacon_erase(const struct term_state *, int, int, int, int);
  47 static void vesacon_write_char(int, int, uint8_t, const struct term_state *);
  48 static void vesacon_showcursor(const struct term_state *);
  49 static void vesacon_scroll_up(const struct term_state *);
  50
  51 static struct term_state ts;
  52 static struct ansi_ops op = {
  53   .erase        = vesacon_erase,
  54   .write_char   = vesacon_write_char,
  55   .showcursor   = vesacon_showcursor,
  56   .set_cursor   = __vesacon_set_cursor, /* in drawtxt.c */
  57   .scroll_up    = vesacon_scroll_up,
  58 };
  59
  60 static struct term_info ti =
  61   {
  62     .cols = TEXT_PIXEL_COLS/FONT_WIDTH,
  63     .disabled = 0,
  64     .ts = &ts,
  65     .op = &op
  66   };
  67
  68 /* Reference counter to the screen, to keep track of if we need reinitialization. */
  69 static int vesacon_counter = 0;
  70
  71 /* Common setup */
  72 int __vesacon_open(struct file_info *fp)
  73 {
  74   static com32sys_t ireg;       /* Auto-initalized to all zero */
  75   com32sys_t oreg;
  76
  77   (void)fp;
  78
  79   if (!vesacon_counter) {
  80     /* Are we disabled? */
  81     ireg.eax.w[0] = 0x000b;
  82     __intcall(0x22, &ireg, &oreg);
  83
  84     if ( (signed char)oreg.ebx.b[1] < 0 ) {
  85       ti.disabled = 1;
  86     } else {
  87       /* Switch mode */
  88       if (__vesacon_init()) {
  89         vesacon_counter = -1;
  90         return EAGAIN;
  91       }
  92
  93       /* Initial state */
  94       __ansi_init(&ti);
  95       ti.rows = __vesacon_text_rows;
  96     }
  97   } else if (vesacon_counter == -1) {
  98     return EAGAIN;
  99   }
 100
 101   fp->o.rows = ti.rows;
 102   fp->o.cols = ti.cols;
 103
 104   vesacon_counter++;
 105   return 0;
 106 }
 107
 108 int __vesacon_close(struct file_info *fp)
 109 {
 110   (void)fp;
 111
 112   vesacon_counter--;
 113   return 0;
 114 }
 115
 116 /* Erase a region of the screen */
 117 static void vesacon_erase(const struct term_state *st,
 118                           int x0, int y0, int x1, int y1)
 119 {
 120   __vesacon_erase(x0, y0, x1, y1, st->cindex);
 121 }
 122
 123 /* Draw text on the screen */
 124 static void vesacon_write_char(int x, int y, uint8_t ch,
 125                                const struct term_state *st)
 126 {
 127   __vesacon_write_char(x, y, ch, st->cindex);
 128 }
 129
 130 /* Show or hide the cursor */
 131 static void vesacon_showcursor(const struct term_state *st)
 132 {
 133   __vesacon_set_cursor(st->xy.x, st->xy.y, st->cursor);
 134 }
 135
 136 static void vesacon_scroll_up(const struct term_state *st)
 137 {
 138   __vesacon_scroll_up(1, st->cindex);
 139 }
 140
 141 ssize_t __vesacon_write(struct file_info *fp, const void *buf, size_t count)
 142 {
 143   const unsigned char *bufp = buf;
 144   size_t n = 0;
 145
 146   (void)fp;
 147
 148   if ( ti.disabled )
 149     return n;                   /* Nothing to do */
 150
 151   /* This only updates the shadow text buffer... */
 152   while ( count-- ) {
 153     __ansi_putchar(&ti, *bufp++);
 154     n++;
 155   }
 156
 157   /* This actually draws it */
 158   __vesacon_doit();
 159
 160   return n;
 161 }
 162
 163 const struct output_dev dev_vesacon_w = {
 164   .dev_magic  = __DEV_MAGIC,
 165   .flags      = __DEV_TTY | __DEV_OUTPUT,
 166   .fileflags  = O_WRONLY | O_CREAT | O_TRUNC | O_APPEND,
 167   .write      = __vesacon_write,
 168   .close      = __vesacon_close,
 169   .open       = __vesacon_open,
 170   .fallback   = &dev_ansicon_w,
 171 };